The wonder of weightless worms

11 July 2012

Many different creatures have joined astronauts in space. Like people, most of them find it hard to adapt to weightlessness. One exception is a tiny worm, known as C. elegans, which seems to do better in orbit than on Earth.

When ESA astronaut André Kuipers first went to the International Space Station (ISS) in 2004, C. elegans was chosen to go with him. The microscopic worms were selected because they were the first complex life form to have all of their genes (the building blocks of their body cells) mapped.

Afterwards, scientists found that seven of the worms’ genes were less active in space. Surprisingly, the worms seemed to function better without them. The results suggested that their muscles were adapting to space conditions. Could spaceflight slow the process of muscle ageing?

C. elegans

Laboratory experiments confirmed that other worms raised without the seven genes also had longer and healthier lives. Since humans share around 55% of their genes with C. elegans, the next step was to find out how human muscle responds to spaceflight.

During his second mission on the ISS, which ended on 1 July, André carried more worms for a follow-up study. But this time the astronaut was studied too. Before the start of his mission, a small piece of muscle was removed from one of his legs and kept for analysis. Scientists are now eager to find out how this sample compares with the muscles that have spent six months in weightlessness. However, unlike the worms, André is being allowed a few weeks to recover from his tiring journey before his muscles go under the microscope.